examples: print the usage message when a required option is missing

While at it specify which option is missing when picoproj fails..

diff --git a/examples/am7xxx-play.c b/examples/am7xxx-play.c
index 38812a4..e958eee 100644 (file)
--- a/examples/am7xxx-play.c
+++ b/examples/am7xxx-play.c
@@ -777,7 +777,8 @@ int main(int argc, char *argv[])
        }
 
        if (input_path == NULL) {
-               fprintf(stderr, "The -i option must always be passed\n");
+               fprintf(stderr, "The -i option must always be passed\n\n");
+               usage(argv[0]);
                ret = -EINVAL;
                goto out;
        }

diff --git a/examples/picoproj.c b/examples/picoproj.c
index 8341527..610e148 100644 (file)
--- a/examples/picoproj.c
+++ b/examples/picoproj.c
@@ -168,7 +168,8 @@ int main(int argc, char *argv[])
        }
 
        if (filename[0] == '\0') {
-               fprintf(stderr, "An image file MUST be specified.\n");
+               fprintf(stderr, "An image file MUST be specified with the -f option.\n\n");
+               usage(argv[0]);
                exit_code = EXIT_FAILURE;
                goto out;
        }